||Yep, and got the job ;-).
Usually, when you do an interview with Microsoft for an internship, you first talk to you recruiter. Expect some general questions like why do you want to work at Microsoft, what was the hardest project you've ever done, etc.
After that, you will speak to one or more people (depending on how you are doing etc, if the first person you talk to is 100% sure they want you, they might have enough, but he might also be 100% sure about not wanting you, so usually you speak to 3 different people or so I think) that will ask you programming questions. It's just a 1 to 1 conversation, somewhere in that persons office, and they ask you to write (pseudo) code on a whiteboard.
It probably depends on which team you are interviewing with, but because you have a blue TC rating, I assume it will be some kind of team where you would require algoritm skills. So, the questions I got where things like:
Write down the code to get the 2 smallest numbers from an array.
So I just did a Sort and then returned the first 2 elements, but then he said:
Ok, now imagine you cannot sort, how would you do it?
So I had to change the code again and again, and I also got some harder questions, but of course you don't need to know hard algoritms by heart. Just speak out loud about what you are thinking, the most important part is that they get an idea about how you are thinking about the problem, not if you solve it 100% correct.
At the end of the day, you will come back to your recruiter (or somebody else in my case, because my recruiter was already gone) to answer questions about how the interviews went. My feedback there was that I had a great day, but spoke to 2 teams that I didn't really want to do an internship with. My recruiter arranged a phone interview 2 weeks later with some team I did want to work, and they hired me! But, I guess most times you will speak to the right teams the first time.
So, that's basically what it's like, I hope it can help you, or maybe other people that read this. Believe me, working at MS will be great!